There are many sleep apps that claim to use the accelerometer, microphone and camera in your phone to record the quality of your sleep, using sleep graphs to show how you slept, but all of them use average sleep patterns. This is based on the idea that interrupting the wrong sleep cycle—when you’re in slow-wave (deep sleep) or REM (dreaming)—can result in a sense of fatigue. But a study published in June in Preventive Medicine Reports, which screened 369 sleep apps available on Android and iPhones, analysed the most popular apps and found that while most help users set sleep-related goals, track and manage their sleep, and even offer white noise or guided meditation, few make use of other methods known to help the chronically sleep-deprived.

“There weren’t a lot of apps that had any information about the benefits of sleep, mentioned health risks associated with not getting enough sleep, and recommended the amount of sleep someone should get on a regular basis,” said Prof. Diana Grigsby-Toussaint from the University of Illinois, US, who led the research, in a press release.

While you can use sleep apps to regulate and discipline your body clock and sleep cycles, you shouldn’t make the mistake of believing these can help you tackle sleep disorders. The only way to accurately measure human sleep today is with the polysomnography test (PSG), a medical process which comprises a series of electrodes placed on the frontal, occipital, temporal and parietal areas of the scalp for one night, to measure brain waves, sleep patterns, sleep stages, oxygen, ECG and leg movements during sleep. “Even with a complete overnight PSG graph, you need an expert to spend almost an hour to analyse it and to be able to report confidentially,” says M.S. Kanwar, senior consultant, critical care, pulmonary and sleep disorders, Indraprastha Apollo Hospitals, Delhi, adding, “Sleep is a very complicated process and so is the methodology to access it.”

“If you do not have any sleep disorders like insomnia or sleep apnea, these apps can help you keep good sleep hygiene, inculcate a habit in you,” says Vivek Anand Padegal, director, pulmonology and sleep specialist, Fortis Hospital, Bengaluru.

In a study published in March last year in the World Journal Of Otorhinolaryngology—Head And Neck Surgery, a review of sleep-analysis smartphone apps found that though most apps provided data on sleep structure, the algorithms they used were not validated by scientific literature or studies. There’s a huge knowledge gap between the technology these apps use and the technology used by sleep experts to help people with sleep problems, the study found.

Smartphones can’t always measure sleep stages accurately—the only way to do that, Dr Padegal explains, is by monitoring brain waves and patterns through electrodes, as doctors do.

The conclusion: Apps need to up the ante if they are to help people sleep. So, go ahead, use them, but remember their limitations. As Dr Padegal puts it, “In the absence of any hard clinical proof or scientific study which shows how these apps work, by themselves they should not be used to replace the council of a doctor.”

The apps listed here can give you a general idea of sleep patterns, and perhaps help you discipline your sleep habits.

Smart alarms

Sleep Cycle alarm clock: Set a time span for when you want to wake up and Sleep Cycle will ring at the exact moment when your sleep cycle is complete. The app uses the phone’s accelerometer and audio recorder to analyse and identify sleep phases and average bedtime, and aims to wake you up at a time when you’re not in deep sleep or in dream mode. Free on Android, iOS (in-app, or additional feature, purchases, Rs50 onwards). Sleepcycle.com.

Sleep Time+: This smart alarm clock uses your phone’s sensors to monitor light- and deep-sleep phases and graphs the data from your phone’s accelerometer. It incorporates an algorithm designed at the US’ Stanford University with the aim of waking you up at the optimal time. In addition, it offers detailed metrics and soundscapes like ocean waves to help you to sleep. But you need to keep your phone unlocked for this to work. $1.99 (Rs130) on iOS. Free on Android (in-app purchases, Rs330 onwards). Azumio.com.

Lulling you to sleep

Pzizz: The Pzizz app offers dreamscapes with hypnosis voice scripts, sound effects, binaural beats and calming music. Set a duration ranging from 10 minutes to 10 hours and Pzizz will construct a unique soundtrack for you every time from its library of built-in media, its algorithms learning from your usage patterns over time. Free on Android, iOS. www.pzizz.com

Noisli: Noisli generates white noise or sounds over a wide frequency range to mask external noise interruptions, to help you relax and doze off. The app comes with an offline soundboard with various types of white noise that you can mix, customize and save for your own use. Fire off the custom mix and set a sleep fade-out timer. Free on Android, iOS. Noisli.com.

White Noise Market: Have a brilliant piece of white noise that will help the world fall asleep? Upload it to the White Noise Market App, a place to share your recordings with the world. The app’s algorithm perfectly loops your audio recordings so you can play relaxing sounds throughout the night. You can also find out what white noise other people use to fall asleep and experiment from their repository of three million sounds. Free on iOS, Android and Amazon. Whitenoisemarket.com.

Digipill: Reduce stress, insomnia, anxiety and fall asleep with the guided meditation sessions and soundscapes of Digipill. The app comes with a few free modules, essentially audio packages you will listen to using your headphones. The rest have to be purchased in-app (Rs50-350). Free on iOS and Android. Digipill.com.

Motionx-24/7: The app records audio clips of when you snore, wake up or move in the middle of the night and builds your sleep pattern, including light-sleep and deep-sleep patterns. It also plays music or white noise to lull you to sleep, analyses your sleep patterns through the night and wakes you up at the best possible moment to make you feel energetic and refreshed. $0.99 on iOS. 24-7. Motionx.com.